Narrow-Bandwidth Blue-Emitting Ag–Ga–Zn–S Semiconductor Nanocrystals for Quantum-Dot Light-Emitting Diodes
Xiulin Xie, Jinxing Zhao, Ouyang Lin, Zhe Yin, Xu Li, Yu Zhang, Aiwei Tang
Abstract
I–III–VI type semiconductor nanocrystals (NCs) have attracted considerable attention in the display field. Herein, we realized the synthesis of narrow-bandwidth blue-emitting Ag–Ga–Zn–S (AGZS) NCs via a facile one-pot method. Intriguingly, the Ag/Zn feeding ratio and Ag/Ga feeding ratio are crucial for the realization of narrow-bandwidth AGZS NCs. By choosing a Ag/Zn feeding ratio of 4:1 and Ag/Ga feeding ratio of 1:8, AGZS NCs demonstrate a typical blue emission at 470 nm with a narrow full width at half-maximum (fwhm) of 48 nm, which is mainly generated from the band-to-hole recombination rather than the donor–acceptor pair (DAP) recombination. Furthermore, a solution-processed quantum-dot light-emitting device based on AGZS NCs exhibits a narrow electroluminescent bandwidth of 53 nm and high luminance over 123.1 cd m–2, as well as a high external quantum efficiency (EQE) of 0.40%. Our work highlights AGZS NCs with high color purity as an important candidate for blue-light-emitting devices.